function Person(name, age){
    this.name = name;
    this.age = age;
}
Person.prototype = {
    say: function(){
        console.log('hello');
    },
    babk: function(){
        console.log('babk');
    }
}
function myNew(fn, ...args){
    let obj = Object.create(fn.prototype);
    // 函数是傀儡.call(obj(this指向谁)， ...args(接受的参数))
    fn.call(obj, ...args);
    return obj;
}
let p1 = myNew(Person, '张三', 18);
console.log(Object.keys(p1), p1.__proto__);